Small underwater sub-wavelength acoustic switching device

The invention discloses a small underwater sub-wavelength acoustic switching device, and belongs to the technical field of underwater acoustic detection and underwater acoustic communication. The device is provided with two parts of acoustic artificial structures, an acoustic grating fixing plate, an acoustic grating supporting plate, a hoisting ring, a stabilizing block, a base, a vertical fixingplate and an acoustic grating rotating circle, wherein the first part of the acoustic artificial structure is a one-dimensional fluid-solid superlattice, and the second part of the acoustic artificial structure is composed of tunable rectangular acoustic gratings periodically arranged in the horizontal direction; round holes which are periodically arranged are formed in the acoustic grating fixing plates; the acoustic grating rotating circle is embedded in the circular hole; a rectangular hole is formed in the acoustic grating rotating circle; the rectangular acoustic grating penetrates through and is fixed in the re